Cellular Protocol & Software Engineer

Precise Systems; Crane (IN); On-site; USD 90,000 - 130,000; Full time

Job summary

Precise Systems seeks a Cellular Protocol & Software Engineer to analyze, develop, implement, and test 3G, LTE, and 5G cellular protocols across lab, simulated, OTA, and field environments at NSWC Crane. In-person work is required.

You will decode signaling across RRC, NAS, PDCP, RLC, MAC, and PHY, and build software in C, C++, and Python for protocol testing. Minimum 3 years in protocol analysis or software development, with hands-on LTE/5G experience and strong programming skills.

Qualifications

• Bachelor's degree required in a relevant engineering/computer field.
• Minimum of 3 years of professional experience in computer design, software development, or computer networks.
• Hands-on experience analyzing or developing cellular protocols at protocol-stack, signaling-message, or packet level.

Responsibilities

• Analyze 3G, LTE, and 5G protocol stacks, signaling flows, and state transitions.
• Decode and evaluate cellular control-plane and user-plane signaling across RRC, NAS, PDCP, RLC, MAC, PHY.
• Analyze 3GPP procedures such as registration, attach, mobility, handover, and session setup.
• Identify protocol fields, timing relationships, and potential vulnerabilities.
• Develop, modify, and maintain software in C, C++, and Python for protocol testing and analysis.
• Capture, decode, inspect, and troubleshoot cellular signaling and packet traffic.
• Develop and execute structured test cases to exercise protocol states and sequences.
• Support laboratory, simulated, OTA, and field testing environments for protocol behavior.
• Correlate RF observations with protocol activity to support analysis and conclusions.
• Prepare test procedures, reports, and engineering recommendations for Government review.

Skills

C

C++

Python

Protocol analysis

Test development

Automation

Education

Bachelor's degree in Computer Engineering, Electrical Engineering, Electronics Engineering, or Mathematics with a concentration in computer science

Tools

Wireshark

OpenAirInterface

srsRAN

Job description

Precise Systems delivers integrated, mission-ready solutions that advance warfighter readiness and strengthen our nation's most critical defense programs. Through the power of our combined capabilities, we provide deep expertise in Advanced Engineering; Digital Transformation; Electromagnetic Warfare; Interactive Training & Simulation; Physical Sciences Research; Platform Lifecycle Support; and Foreign Military Sales. Unified by decades of trusted performance and expanded through strategic growth, our team applies innovative technologies, engineering rigor, and customer-focused execution to solve complex challenges and accelerate mission success. Guided by our commitment to partnership, precision, and performance, we deliver the scalable solutions and technical excellence our customers depend on-today and into the future.

Precise Systems is seeking a Cellular Protocol & Software Engineer to support NSWC Crane's Expeditionary Electromagnetic Warfare mission. This position focuses on the analysis, development, implementation, and testing of 3G, LTE, and 5G cellular protocols in laboratory, simulated, over-the-air, and field environments. The engineer must be able to analyze cellular communications beyond RF spectrum observations by breaking down protocol signaling, message exchanges, information elements, state transitions, and interactions between protocol layers. This is not a traditional cellular network optimization or RF performance-monitoring role. This position requires in-person support.

Duties:

• Analyze 3G, LTE, and 5G protocol stacks, signaling flows, message exchanges, state transitions, and protocol behavior at the packet and message level.
• Decode and evaluate cellular control-plane and user-plane signaling, including interactions among RRC, NAS, PDCP, RLC, MAC, and PHY layers.
• Analyze 3GPP procedures such as registration/attach, authentication, security establishment, session setup, mobility, handover, and connection management.
• Identify protocol fields, information eements, timing relationships, implementation differences, abnormal behavior, edge cases, and potential vulnerabilities.
• Develop, modify, debug, and maintain software in C, C++, and Python to generate, emulate, manipulate, analyze, or test cellular protocol behavior.
• Capture, decode, inspect, and troubleshoot cellular signaling and packet traffic using protocol-analysis, packet-analysis, cellular diagnostic, or comparable engineering tools.
• Develop and execute structured test cases that exercise specific protocol states, message sequences, malformed conditions, implementation behavior, and performance characteristics.
• Support software‑defined, simulated, laboratory, over‑the‑air, and field test environments used to reproduce, stimulate, or assess cellular protocol behavior.
• Correlate RF observations and waveform characteristics with protocol‑layer activity to support technically defensible analysis and test conclusions.
• Prepare test procedures, technical reports, protocol analyses, vulnerability findings, briefings, and engineering recommendations for Government review and decision‑making.

Required Education:

• Bachelor's degree in Computer Engineering, Electrical Engineering, Electronics Engineering, or Mathematics with a concentration in computer science

Required Experience:

• Minimum of three (3) years of professional experience in computer design, software development, or computer networks
• Demonstrated hands‑on experience analyzing or developing cellular protocols at the protocol‑stack, signaling‑message, or packet level.
• Working knowledge of 3GPP cellular architecture and LTE/5G protocol behavior, including RRC, NAS, PDCP, RLC, MAC, and PHY interactions.
• Ability to analyze signaling procedures, message sequences, information elements, state transitions, and interactions between protocol layers.
• Strong programming skills in C, C++, and Python for protocol analysis, test development, automation, or software integration.
• Experience capturing, decoding, and analyzing cellular signaling or packet traffic using protocol-analysis, packet-analysis, diagnostic, or comparable tools.
• Eexperience developing or executing structured laboratory, simulated, over‑the‑air, or field test activities.
• Strong technical‑writing and communication skills with the ability to document findings, conclusions, vulnerabilities, and engineering recommendations.

Desired Experience:

• Experience with cellular protocol development, modem or baseband software, UE/eNB/gNB protocol implementation, protocol conformance testing, or telecom research and development.
• Experience with cellular vulnerability analysis, protocol exploitation, malformed‑message testing, or wireless cyber test environments.
• Familiarity with software‑defined radio and open cellular test platforms or frameworks such as srsRAN, OpenAirInterface, or comparable environments.
• Experience with Wireshark or other cellular protocol decoders, packet‑capture tools, diagnostic logging tools, or signaling‑analysis platforms.
• Experience with Digital Signal Processing, FPGA‑based systems, waveform analysis, RF signal generation, or RF test infrastructure.
• Experience supporting Department of Defense, Navy, Electronic Warfare, cyber, spectrum, or secure laboratory programs.
• Experience with verification and validation, requirements traceability, regression testing, test automation, or Git‑based development workflows.
• Active Secret clearance and ability to support higher‑classification tasking when required.

Must be able to obtain and maintain a Secret security clearance. Due to the sensitivity of customer‑related requirements, U.S. Citizenship is required.

Precise Systems is dedicated to a shared vision and core values of Integrity, Respect, and Responsibility, which foster innovation and drive our continued success in the global marketplace. Precise Systems and its subsidiaries are Equal Opportunity /Affirmative Action Employers. All qualified applicants will receive consideration for employment without regard to race, color, religion, age, sex, sexual orientation, gender identity, national origin, protected veteran status, status as an individual with a disability, or any legally protected status under federal, state, or local law. Visit www.GoPrecise.com for a listing of current openings and our comprehensive, employee friendly benefits summary. Precise Systems participates in E-Verify.